Return visits after emergency department treatment for sickle cell pain crises
Authors: Patrick S. Walsh, David C. Brousseau, Keli D. Coleman
Journal: American Journal of Hematology (2023)

Sickle cell disease (SCD) is the most common inherited blood disorder. In the United States, there are an estimated 90 000 people living with SCD and approximately 40% are children.1 The sickling of abnormal hemoglobin in red blood cells can lead to painful vaso-occlusive crises, resulting in many emergency department (ED) visits and hospitalizations.2 Previous data have shown high rates of rehospitalization or return to the ED after an inpatient hospitalization for people with SCD,2 but there is limited evidence pertaining to return visits for children after discharge from an ED visit for acute SCD pain. Therefore, we sought to determine the frequency of return visits, assess factors associated with return visits, and to describe institutional variation in hospitalization and revisit rates for children treated and discharged from the ED with uncomplicated SCD pain crises. We performed a retrospective cohort study of 40 hospitals in the Pediatric Health Information System (PHIS; Supporting Information Appendix S1), analyzing ED encounters for uncomplicated sickle cell pain episodes for patients <19 years of age between 2017 and 2021. We included children with International Classification of Diseases Tenth Revision discharge diagnosis of SCD (D57.x, except D57.3) who were treated with a parenteral opioid medication. We excluded encounters with complications, defined as encounters with a diagnosis for acute chest syndrome or priapism, and encounters with charges for both a parenteral antibiotic and a blood culture as a surrogate marker for fever. We calculated the number and percentage of index ED encounters with a revisit at 3, 7, and 14 days. We classified each revisit as either an ED revisit or hospitalization, as well as whether it was a revisit for any reason or for an uncomplicated pain episode (using same criteria as study inclusion). To evaluate variation by institution, we summarized the number of encounters, index visit admission rate, and 14-day return visit rate for each hospital. Hospital admission rate was defined as the percentage of encounters meeting study criteria for uncomplicated SCD pain crisis that were hospitalized from the ED (including both inpatient and observation status). Hospital return visit rates were the percentage of encounters resulting in 14-day return visit after ED discharge. We then analyzed factors associated with 14-day return visits after ED treat-and-release for an uncomplicated SCD pain crisis. We included the patient characteristics of age group, sex, and primary insurance as well as the hospital characteristic of admission rate as predictor variables. We used univariate and multivariable generalized linear mixed-effects models to assess associations between predictor variables and all-cause 14-day return visits, using random intercepts for patients within hospitals to account for clustering. There were 30 154 encounters for uncomplicated SCD pain crisis during the study period. Of those, 16 307 (54%) were hospitalized, leaving 13 847 encounters for 5499 unique individuals treated and discharged from the ED included in the analysis (Supporting Information Figure S1). The median age was 12 years (IQR 8–16 years). The cohort was 48% female, 96% Black, and 74% had public insurance (Supporting Information Table S1). Return visits for SCD pain crises treated and discharged from the ED were common. Of the 13 847 included encounters, 4289 (31%) had a repeat ED visit or hospitalization within 14 days. The return visits were a mix of ED treat-and-release encounters and hospitalizations: 15% of index encounters had an ED treat-and-release revisit and 18% had a return visit resulting in hospitalization (some had both). There were 2334 (17%) encounters with a 3-day revisit and 3359 (24%) with a 7-day revisit. Limiting revisits to only the repeat encounters that were for uncomplicated SCD pain resulted in revisit rates of 9.1%, 14%, and 19% at 3, 7, and 14 days, respectively (Table 1). The 40 hospitals included in this study varied widely in numbers of encounters, hospitalization rates, and return visit rates after ED encounters for uncomplicated SCD pain crises. The median hospital index visit admission rate was 57% (IQR: 51%–62%), and range was 25%–82%. All-cause 14-day revisit rates also varied by institution, with a median rate of 29% (IQR: 25%–35%) and range of 10%–45% (Supporting Information Figure S2). There was no significant association between a hospital's number of SCD pain encounters and its admission rate (p = 0.3). In the multivariable models adjusting for clustering by patient and hospital, odds of return visit differed by age, with patients aged 16–18 years having significantly greater odds of return visits (OR: 1.47, 95% CI: 1.27–1.69) compared to children <6 years of age. Differences were not significant for children 6–11 years (OR: 0.93, 95% CI: 0.82–1.07) or children 12–15 years (OR: 1.13, 95% CI: 0.98–1.29). There were no differences between males and females. Compared with the publicly insured, those with private insurance had slightly greater odds of a return visit in univariate model (OR: 1.12, 95% CI: 1.01–1.25), but this was not significant in the multivariable model (OR: 1.11, 95% CI: 1.00–1.24). The admission rate of the hospital where care was delivered was not associated with a significant difference in return visit rates (OR: 1.53, 95% CI: 0.61–3.86; Supporting Information Table S2). These results from this large observational study of 40 EDs across the United States provide new insight into the high rates of repeat encounters after ED treatment for SCD pain. Previous studies have evaluated return visits to acute care settings in SCD, but have generally included adult data, focused on inpatient encounters and rehospitalizations, or included SCD encounters that were not pain-related.2, 3 Data from 2005 to 2006 demonstrated that after an inpatient hospitalization, 8.9% of children <10 years and 16.1% of children 10–17 years had a repeat encounter within 14 days.2 Data from 2016 showed a 30-day readmission rate of 16.7% after hospitalization for pediatric SCD pain.3 In our study, 18% of ED discharges were followed by a hospitalization within just 14 days, which may imply that risk of return visit resulting in hospitalization may be higher after ED discharge than after an index hospitalization. Furthermore, when including repeat ED encounters that did not result in hospitalization (treat-and-release), our overall repeat visit rate was considerably higher (31%). This may suggest that rates of re-hospitalization after inpatient encounters may underestimate the true burden of repeat acute care encounters for children with SCD pain crises. Of note, 39% of 14-day revisits in this study were for reasons other than uncomplicated pain, so it is possible that SCD pain is an indicator for other complications. Some have attempted to reduce utilization by essentially bypassing the ED altogether, treating patients with SCD in day hospitals or observation units,4 but little evidence exists on actual ED-based interventions that might reduce rates of return visits. One potential intervention might be to adjust the criteria for hospitalization, though these data do not support it, as we found no association between hospital admission rates and their corresponding return visit rates. Another intervention could be to tailor treatment based on individual risk of return, potentially focusing on the highest risk older children. Discharge medication prescription is likely important: prescription of non-steroidal anti-inflammatory medications only, without opioids, was an independent predictor of 30-day ED revisits in one study.5 However, there are limited data on optimal discharge care after an ED visit for SCD pain crisis and no clear national guidelines. With nearly one-third of ED discharges having a return visit within 14 days in our study, pain management after an ED visit for SCD pain appears to be a critical gap in the healthcare of children with SCD. Not only do such high revisit rates indicate inadequate pain control, but it is also likely that repeat encounters are more costly than the initial visits.6 Future work should focus on the best practices for care transition between ED clinicians and hematology or primary care providers to ensure adequate pain management after discharge from the ED. This study has several important limitations. Inclusion and exclusion criteria were based on diagnosis and billing codes, so it is possible that some encounters were misclassified. Pain scores and physical exam findings are not part of the data, so we cannot determine severity of symptoms or pain present at discharge. This limits evaluation of clinical factors associated with return visits, as does the lack of information about family support and other socioeconomic factors. Repeat encounters at institutions outside of PHIS hospitals would not be captured in the dataset, so the true rate of repeat acute care visits may be higher than reported in our results. Our analysis comparing hospital admission rates and revisit rates may be limited by differences in case mix; however, our large sample size and modeling adjusting for clustering by individual and hospital are a strength of the analysis. In conclusion, return visits after discharge from the ED were common for children with SCD pain crises. While these rates were high for all children, revisits were most common in older children. Rates of hospital admission and return visits after ED discharge varied widely between hospitals, but there was no association between admission rates and revisit rates. Future guidelines and interventions should focus on improved pain management after ED discharge for children with SCD. Patrick S. Walsh conceptualized and designed the study, carried out the analyses, interpreted the results, drafted the initial manuscript, and reviewed and revised the manuscript. David C. Brousseau and Keli D. Coleman conceptualized and designed the study, interpreted the results, and reviewed and revised the manuscript. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work. The authors would like to thank Lisa Rein of the Department of Biostatistics at the Medical College of Wisconsin for advising on and reviewing the statistical analysis in this study. There are no funding disclosures. The authors declare no conflicts of interest. Data will be made available upon reasonable request. Data S1: Supporting Information. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.